Shearing apparatus

ABSTRACT

Shearing apparatus includes a transversely movable shear assembly having one or more shear blades mounted thereon which shear strip material during traversal thereof with very little or no bending of the strip material. The relative vertical position and depth of cut of the shear blades may be controlled to vary the amount of force and number of passes required to shear the strip material. Where plural passes are required, the transversely movable shear assembly is progressively advanced toward the strip material during each pass to progressively shear the material.

United States Patent Wheeler et al.

Oct. 2, 1973 SHEARING APPARATUS Inventors: Donald J. Wheeler, 7373 Rt. 43,

Kent; Victor Lohrenz, Bedford, both of Ohio 7 H p W Assignee: said Wheeler, by said Lohrenz, Kent,

Ohio Filed?"M hjifif' Appl. No.: 140,723

Related US. Application Data Continuation-in-part of Ser. No. 118,313, Feb. 24, 1971, abandoned, which is a continuation-in-part of Ser. No. 29,430, April 17, 1970, Pat. No. 3,706,25L

US. Cl 83/9, 83/487, 83/495, v 83/636 Int. Cl B26d 3/08 83/8, 9, 487, 595,

Field of Search 7 Primary ExaminerWillie G. Abercrombie [57] ABSTRACT Shearing apparatus includes a transversely movable shear assembly having one or more shear blades mounted thereon which shear strip material during traversal thereof with very little or no bending of the strip material. The relative vertical position and depth of cut of the shear blades may be controlled to vary the amount of force and number of passes required to shear the strip material. Where plural passes are required, the transversely movable shear assembly is progressively advanced toward the strip material during each pass to progressively shear the material.

[56] References Cited UNITED STATES PATENTS 15 Claims, 23 Drawing Figures 3,566,725 ll/1972 Sutyak 83/8 X I I r 1 I I 1 ,n ll u l f8 2 9 E5 l; l t1 -I: 111::rfj? ll:

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PATENTEU 21 3 SHEET 1 [1F 6 INVENTORS 3- I" 'll II II E DONALD 4. WHEELER VICTOR LOHRENZ ATTORNEYS PATENTEDURT 2 m 3.762.249

SHEET 2 BF 6 33' INVENTORS 54:..[5 'oo/v/zw .1. WHEELER VICTOR LOHRE NZ PATENTEDBBT 2191a SHEET BF 6 INVENTORS DONALD J. WHEELER VIC 70/? L OHRE/VZ 11111111 TT I A TTORNE YS PATENTED W 21973 SHEET 5 [IF 6 mO m0.

m om mm INVENTORS DONALD J. WHEELER V/CTUR L UHRE/VZ ATTORNEYS PATENTEDBET 2191s SHEET 6 BF 6 W WL GHQMQ R 2 0 N TEE WM ME w w J R 21 mm v9 WV 0 ATTORNEYS SHEARING APPARATUS CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of United States application of Donald J. Wheeler and Victor Lohrenz, Ser. No. 118,313, filed Feb. 24, 1971, entitled Shearing Apparatus, now abandoned which is a continuation-in-part of United States application of Donald J. Wheeler and Victor Lohrenz, Ser. No. 29,430, filed Apr. 17, 1970, now U. S. Pat. No. 3,706,251, granted Dec. 19, 1972.

BACKGROUND OF THE INVENTION This invention generally relates to shearing apparatus of relatively lightweight and low cost construction for use in precise shearing of strips, sheets and plates of metal or other material such as plastic with very little or no distortion or bending of the material during shearing.

In recent years considerable advancements have been made in reducing the cost and size of strip shearing apparatus by utilizing circular shear blades mounted on carriages for shearing the strip material during traversal of the strip by the carriage. As an example of such a shearing apparatus which has met with considerable success particularly for use in strip processing lines to shear the ends from strips and plates prior to joining, reference may be had to US. Pat. 3,476,000, granted Nov. 4, 1969. However, where more precise shearing is required, up to now it has still been the usual practice to use conventional crop shears despite their relatively high cost and larger size, since the transversely movable circular shear blades have a tendency to bend the material slightly during shearing, which may result in objectionable curling of the shearing edge for certain applications.

SUMMARY OF THE INVENTION With the foregoing in mind, it is a principal object of this invention to provide a shearing apparatus which also utilizes a transversely movable shear assembly for reducing the cost and size of the apparatus but without causing any objectionable bending or distortion of the material during shearing.

Another object is to provide such a shearing apparatus which requires less force than previously required to shear the strip material.

These and other objects of the present invention may be achieved by providing the shearing apparatus with a transversely movable shear assembly on which are mounted one or more shear blades arranged to substantially reduce or completely eliminate the rake angle of the shear blades with respect to the strip material and thereby avoid any tendency of the shear blades to bend the strip material during shearing. In one form of the invention, plural shear blades are mounted on a pivotal support to permit adjustment of the rake angle of the shear blades to suit the material being sheared, and the depth of penetration of the shear blades may be controlled for shearing the strip material in a single pass of the strip material or plural passes. Where plural passes are required, suitable means are also provided for progressively advancing the shear blades toward the strip material during each pass. With the latter construction, the cutting edges of the transversely movable shear blades may be arranged in the same general horizontal plane to completely eliminate the rake angle so that the strip will remain perfectly flat during the shearing operation, or the cutting edges may be in different horizontal planes for progressive shearing of the strip during a single pass.

Where the strip material is sheared in increments, less force is required to move the shear assembly back and forth than is required when the shearing is done in a single pass. The amount of force actually required to reciprocate the shear assembly may be varied by varying the rate of advancement of the shear assembly toward the strip material and by staggering the shear blades so that they successively engage the strip material during such advancement. The transversely movable shear blades may cooperate with a rectangular shear blade to shear the strip during movement thereacross, or the transversely movable shear blades may be made to cooperate with each other to shear the strip. The latter construction has the additional advantage of concentrating the shearing stresses at the immediate shear area, and also facilitates shearing of I-beams and the like.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of a few of the various ways in which the principles of the invention may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS In the annexed drawings:

FIG. 1 is a side elevation view of one form of shearing apparatus constructed in accordance with the subject invention;

FIG. 2 is an end elevation view of the shearing apparatus of FIG. 1 as seen from the plane of the line 2-2 at the right end of FIG. 1;

FIG. 3 is an enlarged schematic illustration showing the manner in which the strip material is sheared during a single pass using the shearing apparatus of FIGS. 1 and 2;

FIG. 4 is a fragmentary side elevation view of another form of shearing apparatus in accordance with this invention, having portions of the transversely movable shear assembly broken away to show the mechanism by which the shear blades are advanced into the strip during reciprocation thereof;

FIG. 5 is a vertical transverse section through the shearing apparatus of FIG. 4, taken on the plane of the line 55;

FIGS. 6 through 8 are schematic illustrations showing alternative arrangements for staggering the shear blades on the shear carriage of the FIGS. 4 and 5 embodiment;

FIGS. 9 and 10 are schematic fragmentary sections through still other shearing apparatus embodiments constructed in accordance with this invention;

FIG. 11 is a fragmentary side elevation view of yet another form of shearing apparatus in accordance with this invention;

FIG. 12 is a fragmentary end elevation view of the apparatus of FIG. 11 as seen from the plane of the line l212 at the left end of the apparatus of FIG. 11;

FIG. 13 is a transverse section through the apparatus of FIG. 11, taken on the plane of the line 13-13 thereof;

FIG. 14 is a schematic fragmentary side elevation view of still another form of shearing apparatus in accordance with this invention;

FIG. 15 is a fragmentary side elevation of yet another form of shearing apparatus in accordance with this invention showing the movable shear assembly in the fully raised position;

FIG. 16 is a fragmentary top plan view of the shearing apparatus of FIG. 15 as seen from the plane of the line 16--16 thereof;

FIG. 17 is a vertical transverse section through the shearing apparatus of FIG. 15 taken on the plane of the line 17-17;

FIG. 18 is a fragmentary vertical transverse section similar to FIG. 17 but showing the movable shear assembly in the lower shearing position;

FIG. 19 is an isometric view of still another form of shearing apparatus in accordance with this invention;

FIG. 20 is an enlarged fragmentary side elevation view of the movable shear blades and supports therefor of the apparatus of FIG. 19;

FIG. 21 is an enlarged fragmentary transverse section through two of the cooperating shear blades of FIG. 20, taken on the plane of the line 21-21 thereof;

FIG. 22 is an enlarged fragmentary transverse section similar to FIG. 21 but showing a modified form of shear blades; and

FIG. 23 is an enlarged fragmentary transverse section through two such cooperating shear blades shown being used to shear l-beams.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1 and 2 there is shown one form of strip shearing apparatus generally identified by the reference numeral 1, including a main frame or housing 2 having a vertical portion 3 on which is mounted an upper shear assembly 4 above strip pass height and a horizontal portion 5 on which is mounted a lower shear assembly 6 below strip pass height.

The upper shear assembly 4 may be of a construction substantially identical to the upper shear assembly which is the subject of the invention disclosed in the application of Donald J. Wheeler and William Adie, U. S. Ser. No. 29,488, entitled Shearing Apparatus, filed Apr. 17, 1970, now U. S. Pat. No. 3,662,639, granted May 16, 1972, and the details thereof do not constitute any part of the present invention. As shown, such upper shear assembly 4 may comprise an elongated frame member 8 which supports a pair of laterally spaced apart jacks 9 connected together as by means of a drive rod 10 and couplings 11 for simultaneous actuation by a single drive motor 14. The rods 12 for the jacks 9 extend through openings 13 in the frame member 8 and are rigidly attached to the vertical portion 3 of the stationary main housing 2, whereby actuation of the jacks 9 will cause the upper shear assembly 4 to be raised and lowered relative to the main housing. A rectangular shear knife or blade 15 carried by the bottom of the frame member 8 presses downwardly against a backup bar 16 on the vertical frame member 3 during lowering of the upper shear assembly 4 to clamp a strip material S therebetween prior to shearing of the strip material, in a manner to be more fully described hereafter.

The lower shear assembly 6 is also of a construction generally similar to the lower shear assembly of the aforementioned copending application of Donald J. Wheeler and William Adie, and includes a carriage 18 mounted on guide rails 19 or the like for transverse movement across the strip material to be sheared. Suitable drive means such as a reversible drive motor 20 may be mounted at one end of the stationary housing 2 for connection to the carriage 18 as by means of a drive chain 21 engaging a drive sprocket 22 on the drive motor 20 and an idler sprocket 23 at the other end of the main housing. As apparent, actuation of the drive motor 20 in opposite directions causes the carriage 18 to move back and forth along the guide rails.

However, instead of providing a single circular shear blade on the carriage 18 for cooperation with the upper rectangular shear blade 15 to shear the strip material during traversal by the carriage as in such aforementioned application, a series of circular shear blades 25 are provided on the carriage 18, each rotatably mounted on horizontally spaced support shafts 26 with their cutting edges 24 lying in the same vertical transverse plane for cooperation with the rectangular shear blade 15 of the upper shear assembly 4. Although the number of circular shear blades 25 of the FIGS. 1 through 3 embodiment may be varied, there are desirably at least three such circular shear blades, and the extent of projection of the uppermost cutting edge of each circular shear blade progressively increases from left to right as seen in FIGS. 1 and 3 to provide for progressive shearing of the strip material during traversal by the carriage. Thus, for example, as best seen in FIG. 3, the circular shear blade 25 at the left end of the carriage 18 penetrates the strip material only slightly; the next shear blade penetrates the strip material to a greater extent; and so on, with the furthest projecting shear blade at the right end of the carriage penetrating the strip material to a sufficient depth to cause the strip material to shear or break completely through during a single pass. The depth of penetration required to obtain shearing may vary anywhere from 30 to 50 percent of the thickness of the strip material or more depending upon the type and thickness of material being sheared.

Because plural circular shear blades 25 are used to progressively shear the strip material, the rake angle defined by the cutting edges thereof is considerably less than if a single circular shear blade were used for shearing the strip material in a single pass, with the result that there is very little bending of the strip material during shearing, and less force is required to move the carriage 18 to shear the strip material.

Preferably, the circular shear blades 25 are all of the same general size and are carried by a pivotal support 27 which may be raised and lowered as by actuation of a jack 28 connected thereto for varying the rake angle of the shear blades to accommodate different types and thicknesses of material. Alternatively, the support 27 for the circular shear blades 25 may be fixed relative to the carriage 18, and their respective support shafts 26 may be vertically staggered to obtain the desired progressive shearing by the circular shear blades, or progressively larger diameter shear blades may be used for accomplishing the same purpose. Electromagnets 29 may also be provided in the housing 8 or adjacent stationary support member 3 or both to resist bowing of the upper shear blade 15 during shearing of relatively thick and wide strip material, as disclosed and claimed in the afore-mentioned Wheeler and Adie application.

One disadvantage of the shearing apparatus of the FIGS. 1 through 3 embodiment is that it will only progressively shear the strip material during movement of the carriage from right to left as seen in FIGS. 1 and 3 due to the disposition of the circular shear blades. However, the furthest projecting circular shear blade adjacent the right end of the carriage 18 may still be used by itself to shear the strip material during movement of the carriage from left to right with some bending and distortion of the strip material. Moreover, it will be apparent that additional circular shear blades 25 may be provided on the carriage 18 to the right of the furthest projecting shear blade as shown in FIG. 7 and properly positioned for progressively shearing the strip material during movement of the carriage in either direction.

In FIGS. 4 and 5 there is shown a modified form of shearing apparatus including an upper shear assembly 4' generally similar to the upper shear assembly 4 of the FIGS. 1 through 3 embodiment, and accordingly the same reference numerals followed by a prime symbol are used to designate like parts. Such shearing apparatus 30 also comprises a lower shear assembly 31 including a transversely movable carriage 32 having a series of circular shear blades 33 mounted thereon for cooperation with the rectangular shear blade 15' of the upper shear assembly 4' for shearing the strip material during traversal of the strip material by the carriage. However, the details of construction and operation of the lower shear assembly 31 of the FIGS. 4 and 5 embodiment are somewhat different from that of the FIGS. 1 through 3 embodiment. First of all, the stroke of the movable carriage 32 of FIGS. 4 and 5 is substantially less, desirably being only slightly greater than the maximum spacing between adjacent shear blades, and the number of circular shear blades is increased so that the strip material is engaged by the circular shear blades across the entire width thereof during such limited movement. Moreover, the carriage 32 is desirably reciprocated back and forth at a relatively high rate during shearing, as for example, 200 strokes per minute, and the circular shear blades 33 are progressively advanced into the work during reciprocation of the carriage for progressively shearing the strip material.

Reciprocation of the carriage 32 may be achieved by connecting one end of the carriage 32 to the outer race 35 of a bearing 36 through a suitable linkage connection 37. The bearing 36 is supported on an eccentrically mounted hub 38 at one end of the stationary frame member 39. Rotation of the hub 38 as by operation of a drive motor 40 coupled to the hub shaft 41 will cause the carriage 32 to be reciprocated back and forth. Wear plates 42 and 43 attached to the bottom and sides of the carriage 32 provide reduced friction and wear during sliding movement of the carriage along a transversely extending guideway 45 on the stationary frame member 39.

During reciprocation of the movable carriage 32, progressive movement of the circular shear blades 33 toward the strip material will occur due to the mounting of the circular shear blades 33 on a support member 46 vertically slidably received between the vertical wear plates 43 on the carriage 32. Interposed between the bottom wear plate 42 of the carriage 32 and support member 46 there is a wedge block 48 having a flat bottom surface 49 slidably engaging the upper flat surface 50 of the bottom wear plate 42 and a tapered upper surface 51 in mating engagement with a correspondingly tapered surface 52 on the bottom of the support member 46. A screw shaft 55 having one end in threaded engagement with the wedge block 48 and the other end extending outwardly from one end of the carriage 32 is received in a tubular member 56 rotatably supported by the stationary frame member 39. The screw shaft 55 is retained against axial movement relative to the carriage 32 by a pair of collars 57 and 58 attached to the screw shaft 55 on opposite sides of the carriage end plate 59, and the projecting end portion 60 of the screw shaft 55 is desirably of rectangular section for sliding receipt in a correspondingly shaped opening in tubular member 56. Turning of the tubular member 56 as by rotation of a hand wheel 61 attached to the outer end thereof will cause simultaneous turning of the screw shaft 55 which moves the wedge block 48 axially relative to the support member 46, forcing the support member 46 and circular shear blades 33 carried thereby vertically inwardly or outwardly along the vertical wear plates 43.

Because the circular shear blades 33 are slowly advanced into the strip material during reciprocation of the carriage 32, all of the circular shear blades 33 may be made to project to the same extent beyond the upper edge of the support member 46 to establish a zero rake angle of the cutting edges with the strip material, with the result that the strip material will remain perfectly flat and be sheared at a uniform rate across the entire width thereof during the shearing operation. However, it will be apparent that the circular shear blades 33 may be staggered if desired for shearing the strip material at different rates to reduce the force required to reciprocate the carriage back and forth. Thus, for example, in FIG. 6 the circular shear blades 33 are shown projecting progressively further from left to right; in FIG. 7 the circular shear blades are shown progressively projecting further from both ends to the center; and in FIG. 8 the circular shear blades are shown progressively projecting further from the center out toward both ends. As apparent, any of these arrangements of the shear blades may be achieved by using the same size shear blades and staggering the mounting shafts therefor, or by using different size shear blades, as desired. The details of construction and operation of the shearing apparatus of FIGS. 6, 7 and 8 may otherwise be the same as that shown and described in the FIGS. 4 and 5 embodiment, and accordingly no further discussion is believed necessary.

Although the use of plural shear blades is preferred, it will be apparent that a single circular shear blade 33 may be provided on the carriage 32 to progressively shear the strip material by progressively advancing the single shear blade into the strip material while the carriage is being reciprocated back and forth. Because the blade 33 only makes a small cut during each pass across the strip material, the amount of bending and distortion of the strip material is considerably less than if the strip material were completely sheared in a single pass using a single shear blade. Of course, where only one blade is provided, its movement must be sufficient to traverse the entire width of the strip material.

Moreover, while use of the upper shear assembly 4' is preferred in conjunction with the lower shear assembly 31 to shear the strip material during traversal of the strip by the lower shear assembly, it will be apparent that the upper shear assembly 4' could be eliminated if the sides 65 of the circular shear blades 33' were beveled and suitable means such as the backup bar 66 of the FIG. 9 embodiment and electromagnets 67 of the FIG. embodiment were used for retaining the strip material against vertical displacement during shearing by the circular shear blades. When a backup bar 66 is used it should desirably be relieved at 68 directly opposite the circular shear blades so as not to interfere with the shearing operation, whereas when electromagnets 67 are used, they may be carried by the stationary frame member 39' on opposite sides of the movable carriage 32'. Energization of the electromagnets 67 pulls the strip material downwardly against the circular shear blades 33'.

In FIGS. 11 through 13, there is shown a shearing apparatus 69 generally similar to that shown in FIGS. 1 through 3, including a vertically movable upper shear assembly 70 and a transversely movable lower shear assembly 71 which cooperate with each other to shear strip material therebetween during traversal of the strip material by the lower shear assembly. However, instead of using circular shear blades 33 on the lower shear assembly 71, there is provided one or more rectangular shear blades 72. Preferably, the rectangular shear blade 72 is of a relatively short length and received in an angularly disposed slot 73 on a holder 74 attached to the lower shear assembly carriage 75 by a mounting bracket 76.

Adjustment of the lateral clearance between the rectangular shear blade 77 of the upper shear assembly '70 and lower rectangular shear blade 72 may be achieved as by providing slotted holes 78 in the mounting bracket 76 for attachment of the mounting bracket to the carriage 75 with the use of fasteners 79. Provision may also be made for adjusting the rake angle of the lower rectangular shear blade 72, as by pivotally mounting the holder 74 to the mounting bracket 76 at 80 and providing a vertical slot 81 spaced from the pivot 80 for receipt of a mounting bolt 82 which releasably clamps the holder in position relative to the mounting bracket. Should the lower rectangular shear blade 72 become damaged or dull during use, it may readily be replaced with a new one, since it is held in place by a single screw 83.

In FIG. 14 there is shown a modified form of shearing apparatus 85 generally similar to the shearing apparatus of FIGS. 11 through 13 except that two lower rectangular shear blades 72' are provided on the blade holder 74, one at each end of the holder for shearing strip material during transverse movement of the carriage 75' in either direction. To facilitate adjustment of the rake angle of the rectangular shear blades 72', a central pivot 86 is desirably provided for the blade holder 74', with arcuate slots 87 on opposite sides of the pivot for receipt of mounting bolts 88 for adjustably clamping the holder in position.

In FIGS. through 18 there is shown still another form of shearing apparatus 90 in accordance with this invention including a main frame or support 91 on which may be mounted a plurality of transversely extending support blocks 92-94 for supporting the strip material S during shearing, in a manner to be described more fully hereafter. One of the support blocks 93 may be notched for receipt of an elongated rectangular shear knife or blade 95 which comprises the stationary lower shear assembly 96, and a lower plate 97 may extend over the support block 94 and abut against the back edge of the rectangular shear knife 95 to provide a flat surface for guiding the strip material over the rectangular shear knife.

Supported above the stationary shear assembly 96 is an upper shear assembly 98 mounted for movement along a pair of l-beams 99 extending transversely of the normal direction of travel of the strip material. Preferably, the upper shear assembly 98 comprises two spaced apart shear carriages 101,102, each having plural cam rolls 103 on opposite sides engaging rails 104,105 on the top and bottom flanges of the l-beams, and connected together by a tie rod 108 extending therebetween as shown, whereby movement of one of the carriages 101 will cause a corresponding movement of the other carriage 102.

Mounted on each of the shear carriages 101, 102 is a cutter housing 109 having a pair of downwardly extending plates 110 suitably fastened to opposite sides and having aligned notches in their lower ends for receipt of the ends of a shaft 111 which is retained in place by shaft retainers 112 (see FIG. 17). Journaled on the shaft 111 is a bearing housing 113 and bearing cap 114 between which is clamped a circular shear blade 11s.

Preferably, both l-beams 99 are mounted for vertical movement to facilitate lowering and raising the upper shear assembly 98 toward and away from the stationary lower shear assembly 96. Attached to the ends of the l-beams 99 are end brackets 116 each having a pair of guide bushing assemblies 1 17 mounted thereon slidable along a pair of guide rods 118 extending upwardly from the main frame 91 at each end of the l-beams. Also mounted on each end bracket 116 is a hydraulic cylinder 119 whose rod 120 extends downwardly therefrom for attachment to the main frame 91, whereby actuation of the hydraulic cylinders 119 in opposite directions raises and lowers the I-beams 99 and upper shear assembly 98 carried thereby.

During lowering of the upper shear assembly 98, an elongated clamp plate 121 carried by one of the I- beams 99 is pressed against the upper surface of the strip material S to clamp the strip material against the lower plate 97 and support blocks 93, 94 therebeneath prior to the shearing operation. The inner face 122 of the clamp plate 121 is desirably of hardened steel and machined to provide a parallel guide surface for accurately locating the circular shear blades 115 with respect to the stationary shear knife 95 by lightly pressing the bearing housings 113 for the circular shear blades against the clamp plate as by using a light spring washer 123 or other suitable device pressing against the bearing caps 114. The bearing housing 113 may also be of hardened steel to minimize wear.

Accurate lateral adjustment of the circular shear blades 115 with respect to the stationary shear knife 95 may be effected by adjusting the lateral position of the clamp plate 121 which is movable toward and away from the circular shear blades by turning one or more set screws 124 which engage the backside of the clamp plate. Jam nuts 125 threaded onto the set screws 124 lock the set screws in place upon tightening the jam nuts.

The housings 109 for the circular shear blades 115 are vertically slidably received between a pair of guide plates 126 on the shear carriages 101,102 and a hydraulic cylinder 127 is mounted on each of the shear carriages above the shear blade housings 109 for controlling the vertical position of the circular shear blades. During the initial lowering of the clamp plate 121 into clamping engagement with the strip material, the hydraulic cylinders 127 which control the vertical position of the circular shear blades 115 relative to the clamp plate 121 are retracted to provide a slight initial clearance between the circular shear blades and strip material. The extent of retraction of the hydraulic cylinders 127 may be varied by adjusting a set screw 128 on each of the circular shear blade cylinders to adjust the stroke of the cylinders during retraction.

After the strip material has been tightly clamped between the clamp plate 121 and lower plate 97, a sequence valve or the like may be actuated by the pressure in the clamp cylinders 119 to admit hydraulic fluid to the cutter cylinders 127, causing the cutter cylinders 127 to advance the circular shear blades 115 into the strip material as the shear carriages 101,102 are reciprocated back and forth to progressively shear the strip material. Reciprocation of the shear carriages 101,102 may be accomplished by a chain drive 129 on the lbeams 99 including a pair of spaced apart sprocket assemblies 130 each having three sprocket wheels 131 and three chains 132 extending from one sprocket assembly to the other and back. Carried by the three chains 132 is a drive pin 133 which extends into a vertical slot 134 in one of the shear carriages 101. The chains 132 are driven by a drive motor 135 mounted on the I-beams and suitably connected to one of the sprocket assemblies 130 thus to reciprocate the shear carriages 101 and 102 back and forth.

During reciprocation of the shear carriages 101,102, the circular shear blades 115 are maintained in proper vertical alignment with respect to the rectangular shear blade 95 by lightly pressing the bearing housings 113 against the inner edge of the clamp plate 121 as aforesaid. Moreover, by providing the cutting edge 136 of the circular shear blades 115 with a single taper in the direction of the clamp plate 121 as shown, the cutting edge acts like a wedge to maintain the bearing housings 113 in engagement with the clamp plate 121 as the circular shear blades are progressively advanced into the strip material as shown in FIG. 18.

The rate of advancement of the circular shear blades 115 into the stripmaterial may of course be varied, as may the rate of reciprocation of the shear carriages 101,102. Moreover, while it is preferred to advance the circular shear blades 115 at the same rate, it will be apparent that they may be advanced at different rates if desired simply by supplying different pressures to the cutter cylinders 127. A limit switch may be provided to indicate when the circular shear blades 115 have sheared through the strip material for automatic raising of the I-beams 99 and shear assemblies 101,102 carried thereby, raising of the circular shear blades 115 within their respective shear carriages 101,102, and stopping of the carriage drive motor 135. Jog switches (not shown) may also be provided to move the shear carriages 101,102 to the ends 137 of the clamp plate 121 which may be relieved as shown to provide additional clearance for changing the circular shear blades 115 when required.

While two such shear carriages 101,102 are shown, it will be apparent that any number of shear carriages and circular shear blades may be provided depending on the width of the material to be sheared and the extent of movement of the shear carriages during reciprocation thereof. Moreover, a single shear carriage may be provided, and more than one circular shear blade may be mounted on each shear carriage if desired.

In FIG. 19 there is shown yet another form of shearing apparatus 140 in accordance with this invention including a carriage 141 suitably mounted on guide rails 142 and the like for movement across the material S to be sheared. The carriage 141 is desirably of generally C-shape including upper and lower horizontal support members 143 and 144 connected together by a vertical support member 145 at one end for maintaining the horizontal support members 143 and 144 in the desired vertically spaced relation. Carried by the upper and lower horizontal support members 143 and 144 adjacent the ends furthest from the vertical support member 145 are upper and lower shear assemblies 146 and 147 which cooperate with each other to shear a workpiece extending between the shear assemblies from the open side of the C-shape carriage during movement of the carriage across the workpiece as explained hereafter. Each of the shear assemblies 146 and 147 includes one or more circular shear blades 148 journal mounted in vertically movable slides 149 received in vertical guides 150 in the horizontal support members 143 and 144 for vertical movement of the upper and lower shear assemblies 146 and 147 toward and away from each other.

The advantage in providing more than one circular shear blade 148 on each of the shear assemblies 146 and 147 is that the extent of projection of the circular shear blades may be varied for progressive shearing during a single pass across a workpiece. Preferably, three such circular shear blades 148 are provided on each of the shear assemblies 146 and 147 with the circular shear blades of each shear assembly being in substantially the same vertical plane and the lower circular shear blades in substantial vertical alignment with re spective ones of the upper circular shear blades as shown in FIG. 20. However, the intermediate circular shear blades desirably project slightly further than the two end shear blades, whereby during movement of the carriage 141 across the work from left to right as viewed in FIGS. 19 and 20, the right-most circular shear blades and intermediate circular shear blades will progressively shear the work while the left-most circular shear blades remain idle, and during return movement of the carriage from right to left, the left-most circular shear blades and intermediate shear blades will progressively shear the work while the right-most circular shear blades remain idle for progressively shearing of the work during movement of the shear carriage in either direction.

While three such circular shear blades are preferred on each shear assembly, it will be apparent that a greater or lesser number of circular shear blades may be provided on each shear assembly if desired, and the extent of projection of the circular shear blades may be the same or varied as previously described by using the same size circular shear blades and staggering the mounting shafts therefor or by using different size shear blades.

Traversal of the work by the shear carriage 141 may be effected by mounting a reversible drive motor 151 at one end of the guide rails 142 for driving a sprocket or drum 152 at such one end, and mounting an idler sprocket or drum 153 at the other end with a chain or cable 154 extending around thesprockets or drums 152 and 153 having their ends connected to opposite ends of the carriage. As apparent, rotation of the drive sprocket or drum 152 in opposite directions causes movement of the shear carriage 141 back and forth along the guide rails 142.

Prior to traversal of the work by the shear carriage 141, the shear carriage may be moved into position adjacent an edge of the work to determine the desired spacing between the circular shear blades 148 on the upper and lower shear assemblies 146 and 147 for effective shearing. In the shearing apparatus embodiment 140 shown in FIG. 19, a common drive motor 155 is desirably provided for raising and lowering of both of the shear assemblies 146 and 147. The common drive motor 155 may be conveniently mounted within thevertical support member 145 and suitably connected to a pair of jacks 156 and 157 in the horizontal support members 143 and 144 by drive connections 158 and 159 for raising and lowering the respective slides 149. The common drive motor 155 may be of the type which when actuated will apply a constant force to the jacks I56 and 157 urging the circular shear blades 148 into the workpiece to the extent possible by the applied force, or the drive motor may be of the type which may be used to advance the circular shear blades by increments into the work after each pass for progressive shearing of the work. Alternatively, a suitable wedge arrangement such as shown in FIGS. 4 and may be provided for incrementally moving the shear assemblies 146 and 147 toward and away from the work.

If a constant force is applied to the jacks 156 and 157 by the drive motor 155 during traversal of the work S by the shear carriage 141, magnetic clutches 160 and 161 are desirably provided in the drive connections 158 and 159 between the drive motor and respective jacks for disengagement of the drive connections when the circular shear blades 148 reach the opposite edge of the work to avoid hanging of the upper and lower shear assemblies 146 and 147 together. Actuation of the magnetic clutches 160 and 161 may be accomplished by providing limit switches 162 or the like ad jacent the edges of the work for engagement by the shear carriage 141. Suitable means (not shown) must also be provided for supporting and clamping the work during shearing.

In FIG. 21 there is illustrated one form of circular shear blades 148 for use with the apparatus 140 of the FIGS. 19 and embodiment having both sides 163 beveled to provide a center cutting edge for the circular shear blades on the upper and lower shear assemblies 146 and 147 which are disposed in vertical alignment with each other as shown for shearing of the work. However, other shear blade configurations may also be used for the'apparatus 140 of the subject invention including a single beveled cutting edge 164 with the bevel reversed on the upper and lower shear assemblies and the cutting edges in alignment with each other as shown in FIG. 22.

Providing upper and lower circular shear blades 148 on the same carriage 141 or on separate carriages for simultaneous movement across the work to be sheared has the advantage of concentrating the shearing stresses at the immediate shearing zone for more effective shearing, and also facilitates shearing of different shape workpieces such as I-beams 165 and the like as schematically shown in FIG. 23 which was ordinarily not possible with prior known shearing apparatus.

We, therefore, particularly point out and distinctly claim as our invention:

1. A shear assembly comprising vertically spaced upper and lower circular shear blades, means mounting said upper and lower circular shear blades for movement back and forth to shear material therebetween during such back and forth movement, and means for progressively advancing at least one of said upper and lower circular shear blades toward the other for progressively shearing the material during such movement of said upper and lower circular shear blades back and forth across the material as aforesaid.

2. The shear assembly of claim 1 wherein said means for progressively advancing at least one of said upper and lower circular shear blades toward the other includes means for applying a constant force urging at least one of said upper and lower circular shear blades toward the other.

3. The shear assembly of claim 1 wherein at least one of said upper and lower circular shear blades is advanced toward the other by increments into the material after each pass for progressive shearing of the material.

4. The shear assembly of claim 1 wherein said means for progressively advancing at least one of said upper and lower circular shear blades toward the other includes wedge means for incrementally moving at least one of said upper and lower circular shear blades toward the other.

5. The shear assembly of claim 1 wherein means are provided for progressively moving both said upper and lower circular shear blades toward each other after each pass to progressively shear material disposed therebet'ween during movement of said circular shear blades back and forth across the material as aforesaid.

6. The shear assembly of claim 5 wherein said means mounting said upper and lower circular shear blades for movement toward each other comprises vertically movable slides on which said upper and lower circular shear blades are mounted, and means for moving said slides toward each other.

7. The shear assembly of claim 1 wherein said means mounting said upper and lower circular shear blades for back and forth movement across the material to be sheared therebetween comprises a carriage for said upper and lower circular shear blades.

8. The shear assembly of claim 7 wherein said carriage is of generally C-shape for receipt of the material to be sheared between said circular shear blades from one side of said carriage.

9. The shear assembly of claim 7 wherein said means mounting said upper and lower circular shear blades for movement toward each other comprises vertically movable slides on which said upper and lower circular shear blades are mounted, and means for moving said slides toward each other.

10. The shear assembly of claim 9 wherein said means for moving said slides toward each other comprises a jackconnected to each slide, and a common drive motor for simultaneously actuating said jacks to move said slides toward each other as aforesaid.

11. The shear assembly of claim 9 wherein said means for moving said slides toward each other comprises a jack connected to each slide, motor means for actuating said jacks, drive connections between said motor means and jacks for transmitting power from said motor means to said jacks, and means for disconnecting said drive connections between said motor means and jacks.

12. The shear assembly of claim 11 wherein said means for disconnecting said drive connections between said motor means and jacks comprises magnetic couplings in said drive connections.

13. The shear assembly of claim 1 wherein there are more than one of said upper and lower circular shear blades to shear material disposed between said upper and lower circular shear blades during such movement of said circular shear blades back and forth across the material as aforesaid.

14. The shear assembly of claim 13 wherein there are three upper circular shear blades and three lower circueach other. 

1. A shear assembly comprising vertically spaced upper and lower circular shear blades, means mounting said upper and lower circular shear blades for movement back and forth to shear material therebetween during such back and forth movement, and means for progressively advancing at least one of said upper and lower circular shear blades toward the other for progressively shearing the material during such movement of said upper and lower circular shear blades back and forth across the material as aforesaid.
 2. The shear assembly of claim 1 wherein said means for progressively advancing at least one of said upper and lower circular shear blades toward the other includes means for applying a constant force urging at least one of said upper and lower circular shear blades toward the other.
 3. The shear assembly of claim 1 wherein at least one of said upper and lower circular shear blades is advanced toward the other by incremeNts into the material after each pass for progressive shearing of the material.
 4. The shear assembly of claim 1 wherein said means for progressively advancing at least one of said upper and lower circular shear blades toward the other includes wedge means for incrementally moving at least one of said upper and lower circular shear blades toward the other.
 5. The shear assembly of claim 1 wherein means are provided for progressively moving both said upper and lower circular shear blades toward each other after each pass to progressively shear material disposed therebetween during movement of said circular shear blades back and forth across the material as aforesaid.
 6. The shear assembly of claim 5 wherein said means mounting said upper and lower circular shear blades for movement toward each other comprises vertically movable slides on which said upper and lower circular shear blades are mounted, and means for moving said slides toward each other.
 7. The shear assembly of claim 1 wherein said means mounting said upper and lower circular shear blades for back and forth movement across the material to be sheared therebetween comprises a carriage for said upper and lower circular shear blades.
 8. The shear assembly of claim 7 wherein said carriage is of generally C-shape for receipt of the material to be sheared between said circular shear blades from one side of said carriage.
 9. The shear assembly of claim 7 wherein said means mounting said upper and lower circular shear blades for movement toward each other comprises vertically movable slides on which said upper and lower circular shear blades are mounted, and means for moving said slides toward each other.
 10. The shear assembly of claim 9 wherein said means for moving said slides toward each other comprises a jack connected to each slide, and a common drive motor for simultaneously actuating said jacks to move said slides toward each other as aforesaid.
 11. The shear assembly of claim 9 wherein said means for moving said slides toward each other comprises a jack connected to each slide, motor means for actuating said jacks, drive connections between said motor means and jacks for transmitting power from said motor means to said jacks, and means for disconnecting said drive connections between said motor means and jacks.
 12. The shear assembly of claim 11 wherein said means for disconnecting said drive connections between said motor means and jacks comprises magnetic couplings in said drive connections.
 13. The shear assembly of claim 1 wherein there are more than one of said upper and lower circular shear blades to shear material disposed between said upper and lower circular shear blades during such movement of said circular shear blades back and forth across the material as aforesaid.
 14. The shear assembly of claim 13 wherein there are three upper circular shear blades and three lower circular shear blades, including two end blades and an intermediate blade which projects further than the end blades for shearing of the material during such movement of said circular shear blades back and forth across the material.
 15. The shear assembly of claim 13 wherein there are a corresponding number of upper and lower circular shear blades respectively in vertical alignment with each other. 